They are Easter eggers. Hatcheries often sell EEs as Americaunas, with the changed spelling, but also sometimes with the right spelling. It is false advertising-- they are counting on people not being able to tell the difference between the two.
For future reference, TSC and other local chick sellers aren't likely to sell purebred Ameraucanas. Pure Ameraucanas will always be listed by color-- black Ameraucanas, silver Ameraucanas, etc. Unless you see them advertised this way they are selling Easter eggers.